Sooner or later "God will have all men to be saved" (1 Timothy 2:4)

It is God's "pleasure" that all mankind be saved.

And "God is operating all in accord with the counsel of His will" (Ephesians 1:11).

Change it to read "in accord with the counsel of what He wants" if you like.

Because God says

"My counsel shall stand.

I will do all my pleasure

(the saving of all mankind is part of the pleasure that God wants)

Yea I have spoken it.

I will also bring it to pass.

I have purposed it.

I will also do it."

Isaiah 46:10,11

Job 23:13 "But He stands alone, and who can oppose Him?

He does whatever he pleases.

(the saving of all mankind is part of what He wants that pleases Him).

Isaiah 55:11 so is my word that goes out from my mouth:

It will not return to me empty,

but will accomplish what I desire

and achieve the purpose for which I sent it.

(the saving of all mankind is part of all of which God desires or wants)

So we see God does all His pleasure, He does whatever He pleases, and His word accomplishes that which He desires.

His pleasure, that which He desires and pleases Him is what He wants.

His will = What He wants

What does He want?

THE SALVATION OF ALL MANKIND

Why will it happen?

Because God Himself will see to it that it gets done.

Any cooperation towards our salvation is the result, not the cause of God laying hold on us by His saving grace and causing Jesus to be "choice" in our heart, just like it was in the case of Lydia and Saul of Tarsus.